Introduction
Protein oxidation is defined as the covalent modification of a protein induced either directly by
reactive oxygen species or indirectly by reaction with secondary by-products of oxidative stress.
Oxidative modification of proteins can be induced in vitro by a wide array of pro-oxidant agents and
occurs in vivo during aging and in certain disease conditions.
There are numerous types of protein oxidative modification. The most common products of protein
oxidation in biological samples are the protein carbonyl derivatives of Pro, Arg, Lys, and Thr. These
derivatives are chemically stable and serve as markers of oxidative stress for most types of ROS.
Many of the current assays involve pre-derivitization of the carbonyl group with
dinitrophenylhydrazine (DNPH) prior to electrophoresis, followed by immunobloting with an anti-
DNP antibody. Unfortunately, this pre-derivatization alters the electrophoretic (and electrofocusing)
properties of proteins. Consequently, it is not possible to directly compare the patterns from
"oxidized" fingerprints with those from "non-oxidized" protein fingerprints. Cell Biolabs’ Protein
Carbonyl Immunoblot Kit has the ability to conduct all derivatization and staining after
electrophoresis and transblotting. This allows one to directly compare oxidized vs. non-oxidized
protein fingerprints.